Dont fallback to HighestResSpec Package if only 1 main package

- fixes #1220

brut.apktool/apktool-lib/src/main/java/brut/androlib/res/data/ResTable.java

@@ -104,6 +104,9 @@ public class ResTable {
         if (pkg != null) {
             return pkg;
         } else {
+            if (mMainPackages.size() == 1) {
+                return mMainPackages.iterator().next();
+            }
             return getHighestSpecPackage();
         }
     }